Insulator.



F. M. SPICER.

INSULATOR.

APPLICATION FILED JUNE 27. 1913.

1,161,080. Patented N0v.23,1915. p

' rnsun Ia. srroun, or owner, iaassacnusnr'rs.

, INSULAJIUE.

application filed Iune 27,1?13. Serial life. '?76,680.

To all whom it may concern;

Be it known that l, FRANK M. Srronn, a citizen of the United States, residing at Quincy, in the county of Norfolk and Corninonwealth of Massachusetts, have invented .certain improvements in Insulators, of

which. the followingdescription, in connection with the accompanying drawings, is a specification, like reference characters on the drawings indicating like parts in the several figures. p

This invention relates to insulators and insulator pins of the character commonly employed in telegraph and power transmission lines and will be herein disclosed as embodied in an insulator and pin designed particularly for use in a feeder line.

In installing feed wire it is the usual practice to run out from a quarter to half a mile of wire stringing it loosely over the cross arms beside the pins of the insulators on which it later will be secured, then to pull up this wire tightly to take out. most of the sag between adjacent poles and finally to tie the wire securely to the insulators. If the entire length of wire to be pulled up lies on a straight part of the feeder line, the pulling up operation is completed while the Wire rests on the cross arms beside the insulator pins and the Wire is then lifted into its proper position on the insulators and is secured to them; but where a curve is included in-the length to be pulled up it is necessary, because of the severe sidewise strain on the insulator pins at the curves, to have the Wire placed in the groove in the side of the insulator Where it later Willbe secured'before the pulling up operation is completed. It is the usual practice, therefore, to put a. comparatively light tension on the Wire, then to place the Wire in the grooves of the insu lators, its lateral pressure on the insulators being suiiicient to hold it there, and then to pull the Wire up to its final tension. During this final pulling up operation the drag of the wire against the sides of the insulators causes theinto rotate on their pins. The type of insulator that has been in common use for this work for a great many years has a tapered and threaded bore receiving a correspondingly tapered and threaded pin, and the rotation of the insulators produced in the manner just described is often sufiicient either to unscrew the insulator completely from its pin, thuspermitting the strain of the Wire to tip it oi the pin and allow the Specification of Letters Patent.

Patented Nov. 23, E915.

Wire to swing away from the pin, or else to screw the insulator down on the pin so tightly that it breaks the insulator. One result is as bad as the other, since in either case the wire must he slacked back sulficiently to allow the insulators to be replaced and the wire to be placed in proper position on them again, and then the pulling up operation must be repeated. lit often becomes necessary for members of the crew to hold certain of the insulators against turning while the Wire is being pulled up to its final tension.

Qhviously, occurrences of the character just described are not only annoying but are expensive, since they Waste much of the time of the entire crew." It is the chief ob ect of the present invention to devise an insulator and insulator pin that will avoid the objections mentioned.

The invention will be readily understood from the following description of one embodiment thereof, reference being made to the accompanying drawing, the figure of which shows, partly in section and partly in side elevation, an insulator and pin constructed in accordance with this invention.

Referring now to the drawing, the insulator pin 2 has a shank portion l designed to be secured in a cross arm or other support 6 in the usual manner, and a body part that projects above the support and is reduced in diameter near its upper end to form a shoulder 8 and an extension 10 projecting above the shoulder, this extension being threaded for at least a portion of its length. This pin preferably is made of metal.

The insulator 12- has a central here to receive loosely the insulator pin 2 and has a shoulder shaped to sit 'on the shoulder 8 of the pin, this construction enabling the insulator to rotate freely on the pin. The insulator also is formed with the usual peripheral groove or seat 24- in which the Wire or cable is placed and has one or more petticoats l6. sulator will be varied to suit the requirements of the particular work for which it is intended. in order to hold the insulator on the pin a cap 18, preferably made of insulating material, is provided with a threaded socket formedin its lower side adapted to screw on to the threaded extension 10 of the insulator pin where it'projects above the insulator. A Washer 20 of fiber, rubber or other suitable material may be interposed (lbviously the design of the in- I between the insulator 12 and the cap 18 to form a yielding cushion between these parts. Preferably the upper end, of the insulator 12 is rounded somewhat and the lower surface of the cap 18' is correspondingly recessed or v concaved'to receive the rounded or projectlng end of the insulatorand prevent the en-' trance of water to the joint betweenfithese members. I

In using this device the usual method of installing wire above described is followed,

the wire or cable being seated in the groove 14 before the final pulling up operation is begun. The cap 18 at this time is screwed only part way on to the extension 10 so that itwill not interfere with the free rotation of the insulator 12. While the wire is being pulled up its drag against the side of the insulator will cause the insulator to rotate on on to the washer 20 clamping the insulator firmly but yieldingly against the shoulder- 8. The wire is then tied to the insulator in the usual manner. I

Preferably the shoulder 8 on the insulator pin and the cooperating shoulder on the insulator are so formed that the insulator is supported out of contact with the cross arm 6; and the shoulder in the insulator is lo cated in the plane of the groove ll, preferably above the middle of the groove so that the larger and stronger part of the pin will extend above this point and afiord ample support against the-sidewise strain that is exerted on the insulator by the wire or cable. v

Having thus described my invention, what I claim as new and desire to secure by Letters Patent of the United States is 7 1. The combination with an insulator, of

a pin projecting loosely and centrally through said insulator and provided with a shoulder and a screw threaded part projecting above the top of the insulator, said insulator having a shoulder resting on the shoulder-of said pin, and an insulator cap screwed on. said threaded portion of the pin, said cap having a concave recess in' its face adjacent rounded part projecting into said recess.

' 2. The combination with an insulator having a circumferential groove formlng a seat v to said-insulator and said insulator having a v for a cable, and having a central bore, said bore being contracted at apoint in the plane of said groove to form an internal shoulder, 1

of an insulator pin projecting loosely through said bore and having a shoulder to support said shoulder of the insulator, said pin having a screw-threaded part projecting above the top of the insulator, and an insulating cap screwed on said threaded part.

of an insulator rotatably mounted thereon, an insulator cap threaded on said pin above "the insulator and constituting the sole means for holding the insulator on the pin, and an insulating washer of yielding material positioned between said cap and insulator.

3. The combination with-an insulator pin,

.4. The combination of an insulator having a circumferential groove forming a seat for acable and having a central bore contracted at a point above the middle of said groove to form an internal shoulder, an insulator pin projecting loosely through vsaid bore and having a shoulder supporting said shoulder of the insulator, said pin also having a reduced threaded extension projecting above said shoulder, and a cap. of insulating material screwed on the threaded part of said extension and serving to hold the insulator on-the pin.

In testimony whereof I have signed my name to this specification in the presence-of two subscribing ,witnesses.

FRANK M. SPICER.

Witnesses:

EMILE H. TARDIVEL, JOHN H. MCCREADY. 

